Dexamethasone and Chemotherapy With or Without Plasma Exchange in Patients With Newly Diagnosed Multiple Myeloma and Acute Kidney Failure

DISEASE CHARACTERISTICS:

* Newly diagnosed multiple myeloma (MM), meeting ≥ 2 of the following criteria:

  * Serum or urine\* paraprotein
  * Bone marrow showing \> 10% plasma cells
  * Lytic bone lesions NOTE: \*The presence of typical myeloma kidney on renal biopsy is considered equivalent to the demonstration of urine paraprotein by electrophoresis
* Acute renal failure attributable to MM, meeting both of the following criteria:

  * Creatinine \> 5.65 mg/dL OR urine output \< 400 mL/day OR requires dialysis
  * Unresponsive to treatment with fluids and/or treatment of hypercalcemia with bisphosphonates
* No significant intrinsic renal disease unrelated to MM

PATIENT CHARACTERISTICS:

* Platelet count ≥ 50,000/mm³
* Bilirubin ≤ 1.5 times upper limit of normal (ULN)
* ALT and AST ≤ 2.5 times ULN
* No contraindications to study medication, including the following:

  * Active or recent peptic ulcer
  * Known significant cardiac insufficiency
  * Allergy to study medications
* Not pregnant or nursing
* Fertile patients must use effective contraception
* No known HIV positivity

PRIOR CONCURRENT THERAPY:

* No prior chemotherapy for MM
* Prior steroid therapy of ≤ 3 days duration for MM allowed